It has been known for a long time that methanol can be obtained with good selectivity by contacting carbon oxides and hydrogen with a catalyst containing copper and zinc.
This reaction has been applied up to now for manufacturing methanol for chemical uses but, with the prospect of more severe requirements concerning motor fuels, methanol manufacture for use as motor fuel additive has a renewed interest.
The main difficulty to overcome, in particular when carrying out the reaction between carbon monoxide and hydrogen, is the removal of heat generated by this highly exothermic conversion.
The conventional use of heterogeneous catalysts in fixed beds is not favorable to a good heat exchange, since it is liable to produce local overheating detrimental to the activity and to the life-time of the catalyst. Generally this disadvantage is avoided by limiting the conversion rate per run and proceeding with high recycling rates.